Web supply apparatus

ABSTRACT

Web supply apparatus for supplying relatively stiff web material such as liner board for a corrugator serves the web from one of two supply rolls. The running web passes through a splicing station and a festoon on its way to the web-consuming machine. The leading end of the ready web is prepared on a web positioning bar away from the splicing station and then carried by the bar to the splicing station while the running web is being consumed. When the roll of running web expires, a control system automatically stops the roll of running web and special pressure pads at the splicing station press the running web and ready web together to make a strong splice between them. Immediately thereafter, a knive fires directly behind the splice, thereby cutting the trailing end of the running web. The pressure pads firmly grip the webs above and below the line of the cut so that the knife slices cleanly through the web. Following this, the roll of ready web is accelerated and the trailing end of the running web pulls the ready web into the festoon which then refills to complete the splicing cycle. When the apparatus incorporates roll stands of the rollout type, the web positioning bars are affixed directly to the roll stands and move in and out of the splicing station with them. When the roll stands are of the fixed type, the positioning bars are moved from a remote loading station to the splicing station by a special transport assembly. Also, the positioning bars can be moved manually from the preparation site to the splicing station if the situation demands it. Thus, the splicing is accomplished at zero speed with maximum reliability, yet the stiff web proceeds uninterruptedly and at constant speed to the corrugator.

BACKGROUND OF THE INVENTION

This invention relates to web splicing apparatus. It relates moreparticularly to apparatus of this type which automatically splices andcuts relatively stiff web material such as liner board for makingcorrugated cardboard. It is designed particularly to splice the leadingedge of a ready web of stiff material to the trailing edge of a runningweb while the web proceeds uninterruptedly and at substantially uniformspeed and tension to a web-consuming machine, e.g., a corrugator,printer, etc.

Web supply apparatus which supplies web uninterruptedly to aweb-consuming machine is, of course, not new. Examples of such machinesare shown in U.S. Pat. Nos. 3,305,189 and 3,414,208. While these priormachines are able to handle relatively limp webs quite easily, making astrong, accurate splice with little or no tail, they are not sosuccessful with the stiffer webs such as liner board. Sometimes thesplice between the trailing end of the running web and the leading endof the ready web may not take or remain secure all across the web, withthe result that the two webs sometimes come apart on the way to theweb-consuming machine. Also, at times, the prior machines of this typedo not cut cleanly all the way through the expiring end of the readyweb, with the result that the splice has a very long tail which may bepulled into the web-consuming machine and interfere with its properoperation.

Another problem with the prior web supply apparatus is that it isdifficult to incorporate them into an existing web processing setupbecause they are rather large and, therefore, cannot fit into theavailable space. In other words, the web supply and splicing apparatusis just one of a series of machines in a production line. All of themachines in the line are extremely large and massive and, therefore,extremely difficult and costly to move. Thus, many existing webprocessing setups cannot be retrofitted with conventional web supplyapparatus having a splicing capability without having to move one ormore of the massive machines in the line in order to accommodate the websupply apparatus.

SUMMARY OF THE INVENTION

The present invention aims to provide web supply apparatus whichdelivers even relatively stiff web such as liner board uninterruptedlyand at a substantially constant speed to a consuming machine such as acorrugator.

Another object of the invention is to provide web supply apparatus whichis able to splice even stiff webs in a reliable and consistent manner.

Still another object of the invention is to provide a web supplyapparatus of the above type which can make a strong, neat splice at zeroweb speed, yet still deliver the web uninterruptedly to a web-consumingmachine.

Still another object of the invention is to provide web supply apparatusof the above type which consistently cuts cleanly through the expiringend of the running web after the splice is made and leaves a small tail.

Still another object of the invention is to provide web supply apparatusof the above type which can be incorporated into many web processinglines without having to substantially rearrange other machines in thatline.

Other objects will in part be obvious and will in part appearhereinafter.

The invention accordingly comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereinafter set forth, and the scope ofthe invention will be indicated in the claims.

In general, the present web supply apparatus delivers web such as linerboard for making corrugated cardboard from one of two rolls, one ofwhich is running and one of which is at the ready. The web from therunning roll travels through a splicing station to be described in moredetail later which is located more or less above and between the tworolls. From there, the web travels to a festoon or accumulator which ispositioned in a generally horizontal plane directly above the two rollsand the splicing station and thence to the web-consuming machine. Withthe elements of the apparatus arranged thusly, the entire machineoccupies a relatively small amount of space as compared with priorapparatus of this type. Consequently, it can be incorporated into anexisting web processing line, for example, under the bridge of acorrugator, without requiring movement of the other heavy machinery inthe line.

While web from the running roll is being consumed, the leading edge ofthe ready roll is prepared by securing it to a mounting bar by means ofa suitable adhesive or the like and applying a strip of double-facedadhesive tape to the edge. Then the mounting bar is carried to thesplicing station in a manner to be described in complete detail later toawait depletion of the running roll.

When the running roll reaches a predetermined minimum diameter, thesplicing cycle commences. First, the roll of running web is braked to asmooth stop. As soon as the roll stops, a pair of spaced-apart opposedpressure pads at the splicing station are projected toward each other.One pad extends directly behind the mounting bar holding the leadingedge of the ready web. The other pad is located behind the running webpassing through the splicing station. As the two pads are urged towardone another, the running web and ready web are pressed together andadhere by virtue of the double-faced, pressure-sensitive tape on theready web.

A knife is associated with each pressure pad at the splicing station,each knife extending the full width of the web. The knife associatedwith the pad behind the running web is actuated automaticallyimmediately following the splice so that it is propelled through therunning web and into a special knife backup which allows the blade tosever the running web, but shields the ready web. The pressure pads arearranged so that, during the cutting operation, the pads securely graspthe ready and running webs both above and below the line of the cut.Since the running web is held firmly at both sides of the knife blade,it is under tension when the cut is made. Consequently, the blade cutsquickly and cleanly and surely through even stiff web material, such asliner board.

All during the splicing operation, the web supply apparatus stilldelivers web at constant speed and tension to the web-consuming machine,drawing on the supply of web stored in the festoon. As soon as theexpiring end of the running web is severed as aforesaid, the roll ofready web is accelerated until the festoon is refilled with web from thenew roll, thereby completing the splice cycle.

The present web supply apparatus thus achieves an excellent seal betweenthe two webs. The joint is clean and uniform across the entire web evenwhen splicing together webs of different widths or different grades.Furthermore, the splice overlap or "tail" is relatively small, on theorder of 6 inches, so that there are no jams further downstream in theline and a printer can actually print right over the splice.

With the present apparatus, there is minimum waste because the systemprecisely controls the point of splice so that there is very little webleft on the expiring roll. In addition, because there are no variationsin the speed of the web fed to the web-consuming machine, the quality ofthe stiff web such as liner board is consistent, thereby minimizing itstendency to warp. This results in fewer problems during the downstreamstacking and finishing operations.

The present web supply apparatus can be used with either the fixedposition or rollout type roll stands for supporting the web rolls. Theonly major difference between the two embodiments involves the specificmeans for moving the web mounting bars to the splicing station as willbe described later in greater detail.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings, in which:

FIG. 1 is a front elevation of web supply apparatus made in accordancewith this invention, and incorporating web stands of the rollout type;

FIG. 2 is an end view thereof;

FIG. 3 is a sectional view on a larger scale showing splicing station ofFIG. 1 apparatus in greater detail;

FIG. 4 is a perspective view with parts broken away on a still largerscale of the splicing station;

FIG. 5 is a view similar to FIG. 1 of an embodiment of the apparatusincorporating fixed position type roll stands;

FIG. 6 is an end view thereof;

FIG. 7 is a front elevational view with parts cut away on a larger scaleshowing the splicing station of the apparatus adapted for manualhandling of the web positioning bars; and

FIG. 8 is a perspective view with parts broken away showing the webpositioning bar used with the FIG. 7 apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Refer now to FIGS. 1 and 2 of the drawings which show the apparatus ofthe present invention with roll stands of the rollout type. It is shownpositioned under the bridge 12 of a conventional corrugator (not shown).One rollout stand indicated at 14 supports a roll 16 of running web W.The other stand 18 supports a roll 22 of ready web W'. Both roll stands14 and 18 are fitted with wheels 26 which ride on tracks 28 in thefloor. Basically, the purpose of the roll stands is to facilitatereplenishing the web supply. When roll 16 expires, the web W is splicedto web W' and the apparatus draws on the web from roll 22. Roll stand 14is rolled along tracks 28 away from the rest of the apparatus, i.e., outof the plane of the drawing figure. Then the core of the expired roll isremoved from the roll stand 14 and replaced by a new roll of web.Following this, the roll stand 14 is rolled back into position as shownin the drawing figure to await depletion of the other web roll 22. Rollstands of this general type are well-known and will not be detailedhere. They are shown, for example, in U.S. Pat. No. 3,488,014, FrenchPat. No. 7505004 and Belgian Pat. No. 763,032.

The present stands differ from the prior ones in that they include apair of upstanding, spaced-apart columns 32 at the ends of the opposingsides of the stands. Three rollers 33a, 33b and 33c are mounted at theupper end of each column (FIG. 4).Iadd.. .Iaddend.Roller 33a isgenerally horizontal, while rollers 33b and 33c are situated at theopposite ends of roller 33a and oriented perpendicular to that roller.The two columns on each stand are arranged to loosely horizontallysupport a long, rectangular web positioning bar; to wit; stand 14supports a bar 34 and stand 18 supports a bar 36 for reasons to be dwelton later. The rollers 33 permit lengthwise and lateral movement of eachbar relative to its supports.

Directly above the roll stands and suspended from bridge 12 is a webaccumulator or festoon indicated generally at 38. Festoon 38 includes apair of transverse, spaced-apart end beams 39 and 40 which, in turn,support a pair of spaced-apart upper rails 41 and a pair of spaced-apartlower rails 42.

A selected number, i.e., three, of idler rolls 44 are rotatively mountedbetween rails 42 near the left-hand end thereof. Also, a guide roll 46is rotatively supported from those rails midway across the festoon.Additional idler rolls 48 are rotatively mounted between rails 41. Inthe present instance, there are two such rolls located above rolls 44.

Festoon 38 also includes a yoke 52 which carries three dancer rolls 54arranged generally in a horizontal plane. Yoke 52 is movable toward andaway from the idler rolls 44 and 48 along a suitable track (not shown).

Web from the running roll, i.e., roll 16, is fed to the festoon 38 byway of splicing station indicated generally at 58, to be described ingreater detail later. The web W is trained around the guide roll 46 andthen looped back and forth between the fixed rolls 44 and 48 and themovable dancer rolls 54, thereby forming a number of bights in thefestoon. Upon leaving the festoon, the web W is trained around a guideroll 61 rotatively supported by bridge 12 and thence passes on into theweb-consuming machine, i.e., a corrugator 63.

During normal operation, the yoke 52 is biased away from the fixed rolls44 and 48 pneumatically, hydraulically or by means of suitablecounterweights so that it tends to assume a position near the right-handside of the festoon. Accordingly, the festoon is able to store arelatively large supply of web, typically on the order of 60 feet ormore. At some time while the running web is being consumed, the rollstand 18 is rolled out and filled with roll 22. The leading edge of webW' is adhered to the positioning bar 36 on stand 18 and prepared withdouble-face, pressure-sensitive tape. Then the stand 18 is rolled backinto the position shown in FIG. 1 to await depletion of roll 16. In thisposition, the bar 36 and the leading edge of the ready web W' aresituated in the splicing station 58.

As soon as the diameter of the roll 16 of running web reaches apredetermined minimum size, the apparatus automatically commences itssplice cycle, whereupon roll 16 is immediately braked to a stop byconventional braking means such as shown in U.S. Pat. Nos. 3,305,189 and3,414,208.

As soon as the running web roll 16 stops, the leading edge of the readyweb W' which has been prepared as aforesaid is bonded to the running webin the splicing station 58 as will be described later in detail and therunning web W is severed just behind the splice. Following this, theroll 22 of ready web is accelerated.

When the web entering the festoon 38 slows and stops as the splice isbeing made, the yoke 52 and dancer rolls 54 move toward the idler rolls44 and 48 as the web-consuming machine uses up the accumulation of webin the festoon. Then as the ready roll 22 accelerates after the splicingoperation, the festoon 38 receives more web than it loses so that theyoke 52 resumes its normal position near the right-hand end of thefestoon, thereby completing the splice cycle.

With the apparatus now consuming the web W' from roll 22, the stand 14can be rolled out and the core thereon replaced by a new roll of web. Inthis case, the leading edge of that web is adhered to the webpositioning bar 34 on stand 14 and prepared with double-faced adhesive.Then the roll stand 14 is moved back into its position shown in FIG. 1to await the expiry of roll 22 and the next splice cycle.

The controls for detecting roll size to actuate the splice cycle, forinitiating the splice at the proper time, for braking and acceleratingthe web rolls, and for controlling web speed and tension generally areall disclosed in U.S. Pat. No. 3,822,838 entitled ELECTRONIC UNWINDCONTROL, which application is owned by the assignee of the presentapplication. Conventional web tension control mechanisms which also canbe used to control the above aspects of the present system are shown inU.S. Pat. Nos. 3,305,189 and 3,414,208, also owned by said assignee.

Turning now to FIGS. 1, 3 and 4, the splicing station 58 is comprised ofa pair of front and rear depending plates 62 and 64 suspended fromfestoon rail 42 and connected by cross beams 65. Each plate 62, 64 isnotched at 66 and 68, respectively, to provide clearance space throughthe centers of the plates. A pair of geneally horizontal channels 72(FIG. 1) and 74 (FIG. 3) are formed on the front and rear plates,respectively, so that they oppose one another inside the splicingstation. These channels form tracks for a pair of carriage assembliesindicated generally at 76 and 78.

Carriage assemblies 76 and 78 are substantially mirror images of oneanother. Therefore, we will use the same identifying numerals for theircommon components. Each carriage assembly includes a depending frontplate 82 (FIG. 1) and a depending rear plate 84 (FIG. 3) arranged justinside end plates 62 and 64, respectively. A pair of rollers 86 on theoutside of each plate 82 is arranged to ride in channel 72 and a similarpair of rollers 88 on the outside of each rear plate 84 are arranged toride in the channel 74 on the rear end plate 64. This enables thecarriage assemblies to move laterally in a generally horizontal planetoward and away from one another.

Connected between the front and rear plates of each carriage assembly isa long, rectangular bar 92. This bar 92 is spaced an appreciabledistance back from the notches 66 and 68 in the end plates. Spaced infront and parallel to each bar 92 is a second bar 94 which is somewhatshorter vertically than bar 92. Each bar 94 is positioned so that itsopposing face is more or less adjacent the edges of notches 66 and 68.Bars 92 and 94 are connected along their lengths by a number ofspaced-apart lateral plates 96 which extend down to the lower edge offront plate 94. Further, a long, rectangular, generally horizontal plate98 is positioned directly below plates 96 and secured to the front andrear plates 94 and 92 to provide an upper guide surface for a knifeassembly indicated generally at 102. The lower face of plate 98 isprovided with a wear surface 104. The lower guide for the knife assembly102 is provided by a similar rectangular plate 106 spaced below andparallel to plate 98. Plate 106 has an upper wear surface 107 and isalso secured to the rear plate 92 as well as to depending carriageplates 82 and 84.

The opposing edges of each lower knife guide 106 are provided with acoextensive rectangular facing plate 110 of the same thickness as plate94. A pressure pad 112 made of rubber or other suitable resilientmaterial covers the entire exposed face of the plate 94. A similar pad114, somewhat thicker than pad 112, covers the exposed face of eachplate 110.

Each carriage assembly 76 and 78 is movable along its track by suitablemeans illustrated here as a hydraulic piston shown generally at 116.Each piston 116 includes a cyliner 117 secured to the stationary beams65 and a piston rod 120 whose free end is connected to the carriage rearplate 92. Each piston 116 is of the double-acting variety so that it canmove its associated carriage assembly between a first position whereinthe pressure pads 112 and 114 are located substantially adjacent theedges of the notches 66 and 68 to a second position where the padsprotrude appreciably into the notches.

Still referring to FIGS. 3 and 4, each knife assembly 102 is comprisedof a long, rectangular block 118 which is able to slide laterally in thespace between the wear surfaces 104 and 107 relative to its supportivecarriage assembly. A long knife blade 122 is secured to the inner edgemargin of the block. The arrangement is such that when the block andknife blade are fully retracted, the edge of the knife blade does notprotrude beyond the pressure pads 112 and 114. On the other hand, whenthe knife is extended, its cutting edge extends out appreciably beyondthose pads.

A knife arrangement employing a special serrated knife and knife backupwhich is particularly suitable for cutting stiff web such as liner boardis disclosed in U.S. application Ser. No. 273,717, filed July 21, 1972,entitled WEB CUTTING KNIFE now abandoned, said application being ownedby the assignee of the present application.

The knife block 118 and blade 122 are moved between their two operativepositions by means of a double-acting piston indicated generally at 124(FIG. 3). Each piston includes a cylinder 126 connected to rear plate 92and a piston rod 128 extending through an opening in that rear plate andconnected to the rear of the knife block 118.

A guide roll 132 is mounted horizontally between the depending carriageplates 82 and 84. Each guide roll 132 is positioned at the lower insidecorners of the end plates so that it can guide web from the adjacentsupply rolls 16 and 22 into the splicing station 58 as best seen in FIG.1.

Still referring to FIGS. 3 and 4, a special knife backup 134 is centeredin the notches 66 and 68. The backup is essentially a long, rectangularrail which is oriented edge-up and suspended horizontally from the frontand rear end plates 62 and 64 by a pair of straps 136 and 138. Thebackup 134 is formed with a pair of long, generally rectangular slots142 and 144, each being directly opposite the adjacent knife blade 122.Each slot 142 and 144 is just wide enough and deep enough to accommodatethe knife blade in its fully extended position.

Assume now that the web W is being consumed from the running roll 16 asshown in FIG. 3. At this point in time, the carriages 76 and 78 are intheir fully retracted positions shown in solid lines in FIG. 3 and theknife assemblies 102 are also in their fully retracted positions.Assume, too, that both of the roll stands 14 and 18 are in theirpositions shown in FIG. 1. Thus, the running web W passes up adjacentthe knife backup 134 and between the web positioning bars 34 and 36 tothe guide roll 46. At the same point in time, the leading end of theready web W' is tacked to the inside face of positioning bar 36 by meansof small strips 152 of double-faced, pressure-sensitive tape, Also, arelatively wide (i.e., 2 inch), long strip 154 of similar tape isadhered to the exposed leading edge margin of the ready web W'.

When the running roll 16 is about to expire, the splice cycle iscommenced as described above. As soon as the roll 16 comes to a stop,the splicer's control system actuates the carriage assembly pistons 116causing the carriage assemblies 76 and 78 to come together as shown indotted lines in FIG. 3, so that their pressure pads 112 engage and pressthe positioning bars 34 and 36 together between straps 136 and 138.This, in turn, forces the web W against the adhesive strip 154 affixedto the leading edge of the ready web W', with the pressure on the twowebs being sufficient to make a strong, reliable bond between them.Immediately following this, the knife piston 124 in the left-handcarriage assembly 76 is actuated by the control system, causing theleft-hand knife blade 122 to project out momentarily beyond itscorresponding pressure pads 112, 114 through the web W and into the slot142 in the knife backup 134.

It is important to note that when this cutting action takes place, thewebs W and W' are grasped firmly between the two positioning bars 34 and36 above the knife. They are also held firmly below the knife betweenthe lower pressure pads 114 and the knife backup 134. As noted above,these lower pads are somewhat thicker than the upper pads 112 tocompensate for the widths of the positioning bars 34 and 36 adjacent thepads 112. Since the webs are held firmly on both sides of the line ofcut, the knife blade is able to cut surely and cleanly through the web Wquite close to the joint. Consequently, the splice is characterized by arelatively short tail, on the order of 6 inches, including the 2 inchjoint. In this connection, it should be mentioned that the tail producedby the left-hand assembly 76 is slightly longer than the one produced bythe right-hand assembly 78 because the two knife blades 122 and theirreceiving slots 142 and 144 are slightly offset one above the other.This offset arrangement and the special knife backup 134 allow theappropriate knife blade 122 to sever only the expiring end of therunning web; the backup completely shields the ready web from the knifeimpact.

As soon as the web W is cut as aforesaid, carriage assemblies 76 and 78retract automatically to their solid line positions shown in FIG. 3 andthe leading edge of the ready web W' is pulled by the running web W towhich it is attached out of the splicing station 58 and over the guideroll 46.

As soon as the festoon is refilled and the splice cycle is completed,the roll stand 14 can be rolled out as described above, therebywithdrawing the positioning bar 34 from the splicing station 58 so thatthe leading edge of a new web roll can be positioned in stand 14 andprepared on bar 34 far away from the heat and congestion at the splicingstation.

Turn now to FIGS. 5 and 6 of the drawings which show a slightlydifferent splicer embodiment incorporating fixed type roll stands. Sincemost of the components of the FIGS. 1 to 4 embodiment of the inventionare found also in this embodiment, we will assign the same identifyingnumerals to them. Aside from the roll stands themselves, the only othermajor difference here involves the means for carrying the positioningbars 34 and 36 from the location where the leading end of the ready webis affixed to them to their position at the splicing station 58.

A conventional fixed type roll stand indicated generally at 170 ispositioned directly below the festoon 38 and splicing station 58. Theroll stand 170 has a pair of spaced-apart chuck supporting arms 172 forholding the running web roll 16. The arms 172 can be lowered whenloading a new roll onto the arms 172, after which the arms can be raisedto lift the roll off the floor. A second similar pair of arms 174 arepositioned at the opposite side of the roll stand supporting the readyweb roll 22.

In this embodiment of the invention, each positioning bar carrying theleading end of the ready web is moved from a web loading position awayfrom the splicing station 58 to the splicing station by positioning bartransport assembly. The transport assembly associated with the roll 16is indicated generally at 176, the transport assembly associated withroll 22 is shown generally at 178. The two transport assemblies aresubstantially mirror images of one another. Accordingly, the samecomponents of each assembly will be denoted by the same identifyingnumeral.

Each web positioning bar 34, 36 is supported at its opposite ends by apair of endless chains 182. FIG. 5 shows the chain and its supportingmechanism which is situated at the front of the apparatus. An identicalchain 182 and supporting mechanism is located at the rear of theapparatus, both chains moving in unison. The lower reach of each chain182 in assembly 176 is trained around a pair of idler sprockets 184 and186 rotatively mounted at the bottoms of depending carriage assemblyplates 82 and 84. Each chain 182 extends up through the splicing station58 and is trained over a sprocket 188 mounted near the top of plate 62or 64. The sprockets 188 are driven by means of a suitable electricmotor drive system 189.

The upper and lower reaches of each chain extend out generallyhorizontally away from the splicing station 58. The upper reach of eachchain in assembly 176 passes over an idler sprocket 192 mounted on adepending plate 194 secured to the festoon rail 42. From there, theupper reach passes over a pair of guides 196 and 198 secured on a plate202 also suspended from rail 42. The lower reach of each chain 182, onthe other hand, passes over an idler sprocket 204 affixed to plate 194and both reaches join at a chain tensioning assembly shown generally at206, there being one at the front of assembly 176 and one at the rearthereof.

Each tensioning assembly 206 is comprised essentially of a pair of idlersprockets 208, 210 mounted on a fixed base 211 and supporting the upperand lower reaches of the chain, respectively. The chain loop beyondthese sprockets passes around a third idler sprocket 212 on a fixture213 which is slidable on a rail 215 toward and away from the fixedsprockets. A compression spring 214 acting between the fixed basesupporting the sprockets 208 and 210 and the movable fixture 213 biasessprocket 214 downward so as to keep the endless chain 182 in a tautcondition. The travel of the movable sprocket 214 also allows the pathof the chain 182 to be altered for reasons to be discussed presently.

The two endless chains 182 in transport assembly 176 are moved in unisonby the driven sprockets 188. By actuating the drive system 189 at theappropriate time either manually or automatically, the chains 182 aremoved counterclockwise to advance the positioning bar 34 from a loadingposition shown at point A in FIG. 5 wherein the bar is shown in dottedlines to a ready position at the splicing station 58 wherein the bar isshown in solid lines.

The web positioning bar 36 associated with the right-hand roll in FIG. 5is moved in exactly the same way by the chains in assembly 178. Thechains are moved clockwise to advance the bar from a loading position atpoint B wherein the bar 36 is shown in solid lines to a ready positionat splicer station 58 wherein the bar is shown in dotted lines. Inactual practice, the driven sprockets 188 in each transport assembly176, 178 are driven in opposite directions in unison by the same drivesystem 189. However, the two assemblies are 180° out-of-phase so thatwhen the positioning bar 34 is in its ready position at the splicingstation 58, the positioning bar 36 is in its loading position at pointB, and vice-versa. A switch 222 is mounted on a bracket 202 in transportassembly 178. This switch is arranged to be tripped by a finger 224projecting out laterally from the chain 182 when the web positioning bar36 reaches its loading position at point B. Of course, this also meansthat the positioning bar 34 is in its ready position at the splicingstation 58. A similar switch 222 and actuator 224 is associated with thetransport assembly 176 to stop the bar 34 at its loading position atpoint A. Thus, each of the switches 222 turns off the drive system 189at just the right times to properly locate the positioning bars 34 and36.

Still referring to FIGS. 5 and 6, assume that the roll 16 is active andthat the running web W is proceeding through the splicing station 58 andover the guide roll 46 and that a new roll has just been loaded onto theroll stand arms 174. At this point, the positioning bar 34 is located atsplicing station 58, while the positioning bar 36 is located at itsready position at point B at the extreme right-hand side of theapparatus. The operator now takes the leading end of the fresh roll andattaches it to the positioning bar 36 as described above. He then placesthe strip 154 of double-faced tape over the exposed face of the leadingedge margin. Next, he energizes the drive system 189 manually, or thismay be done automatically at the proper time with relation to thecompletion of the previous splicing cycle. When the sprockets 188 aredriven, the chains 182 carrying positioning bar 36 carry the leadingedge of the ready web W' along the paths of the chains around the guideroll 132 and to the ready position at splicing station 58. At the sametime, the empty positioning bar 34 is carried counterclockwise by thetransport assembly 176 to its loading position at point A at the extremeleft-hand side of the apparatus. The two bars stop at the proper placesbecause the switch 222 in the transport assembly 176 is tripped at theright time and turns off the drive system 189.

As soon as the roll 16 is depleted, the splicing cycle commencesautomatically as described above, the carriage assemblies 76 and 78moving toward each other as described above. Since these assembliescarry the chains 182, the movable sprockets 212 in the tensioningassemblies 206 move up accordingly. In this embodiment, there is onlyone positioning bar at the splicing station 58 at any given time, e.g.,bar 36. Accordingly, the pressure pad 112 on carriage assembly 76presses directly against the running web W, while the pressure pad 112on assembly 78 pushes the positioning bar 36 carrying the ready webagainst the running web so that a firm seal is formed between the twowebs. As before, the knife blade 122 on carriage 76 is actuated to severthe ready web W just behind the splice, following which the carriageassemblies are retracted and the web W' accelerated up to speed.

It should be mentioned also that since there is only one positioning barat station 58, the pressure pads 112 on the carriage assemblies are madesomewhat thicker than those depicted in FIGS. 3 and 4. Actually, theycan be about the same thickness as the pressure pads 114 shown in thosefigures.

On completion of the splice cycle, the core of the expired roll isremoved from the stand arms 172 and a fresh roll installed. The leadingend of that roll is then affixed to the positioning bar 34 which is nowlocated at the left-hand loading station at point A, to await depletionof the roll 22. Thus, the loading of the web and preparation of itsleading end can be done at a location considerably away from the heatand confinement associated with the splicing station. Therefore, the webcan be prepared more carefully and better splices obtained.

FIG. 7 illustrates still another embodiment of the apparatus which canbe used in conjunction with most types of roll stands. In thisembodiment, the positioning bar carrying the leading edge of the readyweb is moved manually to the splicing station 58. A typical positioningbar is illustrated in FIG. 8. It is comprised of a hollow, generallyrectangular box frame 260. The front face of the box frame is faced witha resilient pad 262 of rubber or the like. Attached to the opposite endsof the frame are a pair of relatively long, generally rectangular straps264 and 266 which project out from the ends of the frame. These strapsare made of a berylium copper alloy which is quite strong yet quiteflexible so that they will allow the bars to be pressed together to makea splice. A pair of elongated slots 274 and 276 are formed in the strapsto support the bar at splicing station 58 as will be described presentlyand a pair of handles 268 and 272 are affixed to the free ends of thestraps so that it can be carried easily. This same type of bar withoutthe handles can be used with the FIGS. 1-4 embodiment of the apparatus.

Splicing station 58 is more or less the same as the one depicted inconnection with the FIGS. 1-4 embodiment of the invention, except thatprovision is made for supporting the positioning bars which are carriedmanually to the splicing station 58. More particularly, a pair ofidentical, horizontally oriented slides 282 are mounted on the outsideof front end plate 62 at the opposite edges of notch 66. Each slideslidably supports a strap or retainer 284. The end of the strap 284facing the notch has a cutout or notch 286 extending down from its topedge. Each strap is arranged to project through the slot 274 in the webpositioning bar shown in FIG. 8 with the top edge of the slot seating inthe notch 286. Each strap 284 is biased away from notch 266 by acompression spring 288 acting between the slide 282 and a washer 292mounted on the end of the strap and retained there by a pin 294extending through the end of the strap. The straps 284 affixed to plate62 are designed to support one end of a pair of positioning bars 34 and36 and an identical arrangement affixed to the outside of the rear endplate 64 supports the other ends of these bars in exactly the same way.

FIG. 7 shows one positioning bar 34 supported by straps 284 at theleft-hand side of the splicing station 58. The running web W which wasoriginally carried by this bar passes up through the station and overroll 46. The leading end of the ready web W' has already been affixed tothe other positioning bar 36 and that bar has been carried by two menstanding in front of and behind the apparatus to the splicing station58.

To facilitate mounting the bar, a pair of guide plates 298 are affixedto end plates 62 and 64 opposite the ends of the knife backup 134.Additional guide plates 302 are attached to plates 62 and 64 adjacentthe edges of the notches 66 and 68. The web positioning bar 36 is slidup into the space between the guide plates 298 and 302 and the bar ishooked up onto the notched straps 284 to position the bar so that theleading end of the ready web is in position for the next splice. A tophorizontal guide plate 304 is attached to plates 62 and 64 at the topsof each notch 66 and 68 to provide a guide for the positioning bars sothat they cannot cock.

When the running web W is depleted, the web W stops and the carriageassemblies 76 and 78 are moved toward each other as described above.This pushes the positioning bars 34 and 36 together, this movement beingaccommodated by the slidable straps 284 to which the bars are connected.As soon as the bars press together, the running web is adhered to theready web W', whereupon the running web is cut just behind the splice.Following this, the carriage assemblies retract, as do the positioningbars, due to the return bias afforded by the compression springs 288.The ready web W' is now pulled out of the splicing station 58 by thetrailing end of the running web. Finally, the ready web roll isaccelerated up to speed, completing the splicing cycle.

At any time after this, the positioning bar 34 can be removed manuallyfrom the splicing station 58 and outfitted with the leading end of a newready web and returned to its position at station 58 to await the nextsplice. Except for the handling of the positioning bars then, the FIG. 7apparatus is more or less the same as the other two embodiments.Therefore, it affords the same advantages in terms of the speed andreliability of the splice. Further, this embodiment is especiallysuitable when retrofitting existing apparatus where working space is ata minimum.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above construction withoutdeparting from the scope of the invention, it will be intended that allmatter contained in the above description or shown in the accompanyingdrawings be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed.

I claim:
 1. Web supply apparatus comprisingA. a first source of web, B.a second source of web, C. an inaccessible splicing station throughwhich web travels alternately from the first and second sources, saidsplicing station including1 . a first pressure pad,
 2. a second pressurepad, said pads being movable toward and away from one another,
 3. meansfor moving the pressure pads toward and away from one another inresponse to a command,
 4. a first knife assembly associated with thefirst pressure pad, said knife assembly including a first blade movablefrom a retracted position out of the path of web from the first sourcethrough the splicing station to an extended position wherein it projectsthrough the path of web from the first source through the splicingstation,
 5. a second knife assembly associated with the second pressurepad, said second knife assembly including a second blade movable from aretracted position out of the path of web from the second source throughthe splicing station to an extended position wherein it projects throughthe path of web from the second source through the splicing station,each said pressure pad extending above and below the corresponding knifeassembly so that when the two pads come toward one another, they retainthe web on both sides of the cutting knife blade, and
 6. means formoving the two blades between their two positions, D. means for guidingweb from one of the sources through the splicing station between the twopads, E. a loading station remote from the splicing station at alocation accessible to an operator, F. means for moving the leading endof the web from the other source from the loading station to a positionat the splicing station between the two pressure pads, G. control meansfor commanding the pressure pad moving means to move the pressure padstoward one another so that the web from the one source is pressedagainst the leading edge of the web from the other source so that thetwo become joined, and H. means for commanding the blade moving meanswhich moves the blade adjacent the path of the web from the one sourceto move to its second position while the pads are moved toward oneanother so that said blade severs the web from the one source justbehind its joint to the web from the other source.
 2. The web supplyapparatus defined in claim 1 and further including a knife backuppositioned directly between the two knife assemblies against which thecutting knife blade acts when cutting the web from the one source, saidknife backup also shielding the web from the other source from saidcutting knife blade during the cutting operation.
 3. Web supplyapparatus as defined in claim 2 wherein the backup is comprised of arail extending parallel to the knife blades, said rail havingA. a firstblade receiving slot directly opposite the first knife blade and asecond blade receiving slot directly opposite the second knife blade,said first and second knife blades and their slots being offset relativeto one another.
 4. Web supply apparatus as defined in claim 1 andfurther including a web accumulator located downstream from the splicingstation and further including means for stopping the one source of webso that a joint can be formed at zero web speed, the accumulatorproviding the web required by a downstream web-consuming machine whilethe incoming web is stopped.
 5. The web supply apparatus defined inclaim 1 wherein the means for moving the leading end of the web from theother source from its loading station to the splicing station iscomprised ofA. a bar to which said leading end is affixed, and B. meansfor removably locating the bar at the splicing station between thepressure pads.
 6. The web supply apparatus defined in claim 5 whereinthe locating means includes a pair of retainers at the splicing stationfor retaining the opposite ends of the bar between the pressure pads. 7.The web supply apparatus defined in claim 6 wherein the retainers aremovable along with the associated pressure pads.
 8. The web supplyapparatus defined in claim 5 whereinA. the first and second web sourcesare mounted on roll stands of the rollout type, and B. the bar locatingmeans is comprised of means on each roll stand for supporting the bar towhich the leading end of the web from the other source is affixed sothat when the roll stand supporting the other source is moved to itsnormal position for feeding web, the positioning bar supported by thatstand properly locates the leading edge of the web at the splicingstation beween the pads.
 9. The web supply apparatus defined in claim 5wherein the bar locating means includesA. transport means connected toeach web positioning bar, said transport means communicating between theweb loading station and the splicing station, and B. means for drivingthe transport means so as to move the positioning bar between its twostations.
 10. Web supply apparatus comprisingA. a first source of web,B. a second source of web, C. a splicing station not convenientlyaccessible to an operator, said splicing station including1. firstpressure applying means,
 2. second pressure applying means, saidpressure applying means being movable toward and away from one another,3. a first knife assembly associated with the first pressure applyingmeans, said first knife assembly including a first blade movable from aretracted position to an extended position wherein it projects beyondthe first pressure applying means toward the second pressure applyingmeans,
 4. .Iadd.a .Iaddend.second knife assembly associated with thesecond pressure applying means, said second knife assembly including asecond blade movable from a retracted position to an extended positionwherein it projects beyond the second pressure applying means toward thefirst pressure applying means, D. means for moving the leading end ofthe web from one of the sources from an .[.inaccessible.]..Iadd.accessible .Iaddend.loading station to a position at the splicingstation between the two pressure applying means, said means for movingthe leading .[.eand.]. .Iadd.end .Iaddend.of the web from each sourcefrom its loading station to the splicing station being comprised of1. a.[.movable.]. bar to which said leading end is affixed, and
 2. means forremovably locating the bar at the splicing station between the pressureapplying means, E. means for moving the pressure applying means towardand away from one another to splice webs trained between them, and F.means for moving the first and second blades between their twopositions.
 11. The web supply apparatus defined in claim 10 wherein thelocating means are comprised of retainers at the splicing station forsupporting the bar between the pressure applying means.
 12. The websupply apparatus defined in claim 10 whereinA. the first and second websources are mounted on roll stands of the roll-out type, and B. the barlocating means are comprised of means on each roll stand for supportingthe bar to which the leading end of the web from a source is affixed sothat when the roll stand supporting that web end is moved to its normalposition for feeding the web, the positioning bar supported by thatstand properly locates the leading end of that web at the splicingstation between the pressure applying means.
 13. The web supplyapparatus defined in claim 10 wherein the bar locating means includeA.transport means connected to each .[.web positioning.]. bar, saidtransport means communicating between each web loading station and thesplicing station, and B. means for moving the transport means so as tocarry each .[.positioning.]. bar between its two stations.
 14. The websupply apparatus defined in claim 10 wherein the pressure applying meansextend above and below the corresponding knife blade so that when thepressure applying means come together, they grip the web between them onboth sides of the blade.
 15. The web supply apparatus defined in claim13 and further including means for controlling the transport means so asto locate each .[.positioning.]. bar at one of its two stations.
 16. Theweb supply apparatus defined in claim 13 wherein the transport means arecomprised ofA. a chain loop extending between one said loading stationand the splicing station, and B. means for driving the chain so that the.[.positioning.]. bar connected thereto is carried by the chain betweenthe two stations.
 17. The web supply apparatus defined in claim 11wherein the bar includes a pair of flexible, resilient end extensionssecured to the retainers to permit the bar to flex relative to theretainers.
 18. The web supply apparatus defined in claim 13 and furtherincluding means for adjusting the path of the transport means tocompensate for the change in said path which occurs when the pressureapplying means are moved.
 19. Web supply apparatus comprisingA. a firstsource of web, B. a second source of web, C. a splicing station throughwhich web travels alternately from the first and second sources, saidstation including,1. first pressure applying means, and
 2. secondpressure applying means, said pressure applying means being movabletoward and away from one another, D. a first knife assembly, said firstknife assembly including a first blade movable from a retracted positionout of the path of the web from the first source through the splicingstation to an extended position wherein it projects into the path of theweb from the first source through the splicing station, E. a secondknife assembly, said second knife assembly including a second blademovable from a retracted position wherein it is out of the path of theweb from the second source through the splicing station to an extendedposition wherein it projects into the path of the web from the secondsource through the splicing station, said pressure applying meansextending upstream and downstream relative to their corresponding knifeblades so that when the pressure applying means are moved to theirextended positions, they grip the web between them on both sides of theblades, F. means for moving the pressure applying means toward and awayfrom one another to splice webs trained between them, G. means formoving the first and second blades between their two positions, and H. aweb accumulator located downstream from the splicing station, saidaccumulator providing the web required by a downstream web-consumingmachine while the incoming web is temporarily gripped by the pressureapplying means. .Iadd.
 20. Web supply apparatus comprising A. a webaccumulator; B. a splicing station located directly underneath theaccumulator that is not readily accessible to an operator; C. a pair ofroll stands of the roll-out type for supporting a pair of web rolls oneof which is expiring into the accumulator, the other of which is at theready, each said stand being movable generally parallel to the axes ofthe rolls between said splicing station and a loading station adjacentthe accumulator that is readily accessible to the operator, D.positioning means supported on each roll stand for positioning theleading edge of the ready web when the roll stand supporting the readyweb is located at its loading station; E. means supporting the rollstand containing the ready web for movement to the splicing station sothat the leading edge of the ready web is positioned directly oppositethe expiring web, and F. means permanently suspended from the overheadaccumulator at the splicing station for pressing the expiring web andready web together to splice them so that web can proceed continuouslyinto the overhead accumulator. .Iaddend..Iadd.
 21. The web supplyapparatus defined in claim 20 and further including means permanentlysuspended from the overhead accumulator for severing the trailing end ofthe expiring web upstream from said splice. .Iaddend. .Iadd.
 22. The websupply apparatus defined in claim 20 wherein each positioning meanscomprises an elongated rigid bar extending the full width of the webproceeding into the accumulator. .Iaddend.